Involvement of the p110 alpha isoform of PI3K in early development of mouse embryos.
Class I of phosphoinositide 3-kinases (PI3Ks) is characterized as a group of intracellular signal proteins possessing both protein and lipid kinase activities. Recent studies implicate class I of PI3Ks acts as indispensable mediators in early development of mouse embryos, but the molecular mechanisms are poorly defined. In this paper, mouse one-cell embryos were used to investigate a possible contribution of the catalytic subunit of PI3K, p110 alpha, to cell cycle progression. The expression level of p110 alpha was determined in four phases of one-cell embryos. Silencing of p110 alpha by microinjection of p110 alpha shRNA into one-cell embryos resulted in a G2/M arrest and prevented the activation of Akt and M-phase promoting factor (MPF). Further, microinjection of the synthesized mRNA coding for a constitutively active p110 alpha into one-cell embryos induced cell cleavage more effectively than microinjection of wild-type p110 alpha mRNA, whereas microinjection of mRNA of kinase-deficient p110 alpha delayed the first mitotic cleavage. Taken together, this study demonstrates that p110 alpha is significant for G2/M transition of mouse one-cell embryos and further emphasizes the importance of Akt in PI3K pathway.
Xu
Xiao-Yan
XY
Department of Biochemistry and Molecular Biology, China Medical University, Shenyang, Liaoning, China.
Zhang
Zhe
Z
Su
Wen-Hui
WH
Zhang
Yang
Y
Feng
Chen
C
Zhao
Hong-Mei
HM
Zong
Zhi-Hong
ZH
Cui
Cheng
C
Yu
Bing-Zhi
BZ
D000818:Animals; D002453:Cell Cycle / Q000502:physiology; D058534:Class I Phosphatidylinositol 3-Kinases; D004622:Embryo, Mammalian / Q000201:enzymology / Q000502:physiology; D005260:Female; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism*; D000090204:Mesothelin; D051379:Mice; D019869:Phosphatidylinositol 3-Kinases / Q000235:genetics / Q000378:metabolism*; D011247:Pregnancy; D051057:Proto-Oncogene Proteins c-akt / Q000235:genetics / Q000378:metabolism; D034622:RNA Interference
D058534:Class I Phosphatidylinositol 3-Kinases; D007527:Isoenzymes; D000090204:Mesothelin; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt; C000715528:Msln protein, mouse; C509622:1-phosphatidylinositol 3-kinase p110 subunit, mouse